This project addresses the process development and evaluation of an extremely flexible, Parylene C, micro-ribbon cable that is both biocompatible and biostable. Such a cable would be employed to link micro-electrode arrays with percutaneous connectors as well as with other in vivo micro-electronic arrays and modules. The key innovation is the approach utilized to form a monolithic structure with the array and connector directly incorporated into the ribbon cable. Thus there is no need to connect the cable to the array and connector after its synthesis. The primary advantages are extreme flexibility and low modulus resulting in easy placement of the electrode array and minimal to no residual tethering forces exerted on the array in vivo. A third advantage is the wide range of cable designs that can be easily and inexpensively fabricated using MEMs photolithographic processes. After process development validations will focus on designs for enhanced flexibility and stress relief as well as in vitro testing of electrical and mechanical properties. The key criteria for success are to develop a method of manufacturing a monolithic ribbon cable structure followed by evaluation, of the cable in terms of acceptable flexibility (as determined by key neuroscience researchers), mechanical and electrical stability in accelerated in vitro testing and finally feasibility and ease of manufacture at an acceptable cost.